KR101013144B1 - An inertial electrostatic confinement fusion device with an electron source - Google Patents

Abstract

The present invention relates to an inertial electrostatic fusion device equipped with an electron source, and more particularly, by mounting an electron source inside a grid electrode where positive space charges are accumulated by ions focused to the center of the grid electrode. By supplying electrons to the center of the electron source, the electron source can increase the neutron yield by effectively canceling the positive (+) space charge accumulated on the electrode center side and minimizing dispersion due to the refraction of the ion beams accelerated to the center. The inertial electrostatic fusion device is mounted.

The present invention provides a cylindrical vacuum chamber, a cylindrical electrode provided on the inner wall of the vacuum chamber and grounded through the vacuum chamber, a grid electrode positioned in an inner center of the vacuum chamber and formed in a cylindrical lattice structure; An inertial type equipped with an electron source, the feedthrough being provided at one side of the vacuum chamber and including a feedthrough for applying a negative high voltage to the grid electrode, and an electron source for supplying electrons into the cylindrical grid electrode Provided is an electrostatic fusion device.

Inertial electrostatic fusion device, IEC, grid electrode, electron source, space charge offset, neutron yield

Description

An inertial electrostatic confinement fusion device with an electron source

The present invention relates to an inertial electrostatic fusion device equipped with an electron source, and more particularly, by mounting an electron source inside a grid electrode where positive space charges are accumulated by ions focused to the center of the grid electrode. By supplying electrons to the center of the electron source, the electron source can increase the neutron yield by effectively canceling the positive (+) space charge accumulated on the electrode center side and minimizing dispersion due to the refraction of the ion beams accelerated to the center. The inertial electrostatic fusion device is mounted.

The production of neutrons up to now has been mainly limited to large devices such as nuclear reactors and large accelerators, and their application has therefore been very limited. However, with recent advances in science and technology, neutrons such as neutrons have begun to be applied to many basic research and industries. Nuclear neutron generation technology is the core technology for biotechnology and new materials research, and it can help develop new medicines and treatments by revealing the function and structure of protein. Change research is the driving force behind the development of new materials in various industries. In addition, it can be used to analyze samples that could not be solved by general chemical methods, nondestructive inspection to check the integrity of key parts of aircraft or automobiles, and to produce various radioisotopes required for the industry. Big.

Using neutrons, you can accurately identify items that were not previously searched by X-Ray when searching baggage at ports or airports.In addition, neutrons can be accurately and effectively surveyed by numerous mines buried in the DMZ or international conflict zones Can be found. In addition, by producing a high-performance nuclear magnetic beam generator that can operate for a long time, it is possible to apply medical radioisotope production or cancer treatment method using Borne Neutron Capture Therapy (BNCT), which has been limited to conventional accelerators. Will be.

In line with the application of these neutrons, methods for generating neutrons in various ways have begun. [Table 1] is a table comparing neutron yield and advantages and disadvantages of various kinds of neutron generators currently used.

Neutron yield [n / s] Advantages Disadvantages nuclear pile ~ 10 ¹⁵ (continuous) High neutron Pulse control not available,
Large device Accelerator ~ 10 ¹⁰ (continuous) High neutron
Pulse control possible Large device
Low flexibility Isotope (252cf) ~ 10 ⁷ (continuous) Compact, portable Pulse control not possible Small ion source ~ 10 ¹⁰ (continuous) Compact, pulse controlled Short life span (target: 600 hours) D-D, D-T tube ~ 10 ¹⁰ (continuous) Compact, portable
Pulse control possible Short life (500 hours)

As shown in Table 1, devices capable of generating high-energy nuclei in MeV units include an accelerator, a reactor, an isotope, and a fusion device using a small ion source. However, in the case of nuclear reactors and accelerators, the construction cost is enormous, and the apparatus is large, which is limited in terms of mobility and flexibility, and isotopes are difficult to manage or control because nuclei are generated by natural decay. Small ion sources can generate neutrons relatively efficiently, but there is a limit to stable operation for a long time due to target heat and lifetime problems. DD and DT tubes have been studied for the purpose of generating small mobile neutrons. Is released in the form of products, but there are problems such as relatively low neutron flux and short lifespan.

In order to solve this problem, research on inertial electrostatic confinement (IEC) has been actively conducted. Inertial electrofusion fusion devices suffer from a previously problematic target because high-energy deuterium (or helium ( ³ He)) ions produce nuclei such as neutrons and protons, resulting in nuclear reactions with plasma or gas targets inside the device. Overheating problems can be greatly reduced. In addition, since the structure is simple and the device can be miniaturized, the device is easy to move and install, and the user is easy to operate and maintain.

1 is a plan view showing the configuration of a conventional inertial electrostatic fusion device.

As shown in FIG. 1, the conventional inertial electrostatic fusion device is a cylindrical (or spherical) vacuum chamber 110, a cylindrical (or spherical) electrode 120 is installed in a grounded state on the inner wall of the vacuum chamber 110. ), The grid electrode 130 is positioned in the center of the chamber and configured to have a cylindrical (or spherical) lattice structure, and a power supply 140 for applying a high negative high voltage to the grid electrode.

With this configuration, a plasma is generated inside the chamber due to a strong electric field formed between the grounded cylindrical electrode and the grid electrode to which a negative high voltage is applied, and the ions present in the chamber are accelerated toward the grid electrode located in the center of the chamber. do. The ions accelerated toward the grid electrode pass through the grid electrode due to the transparency of the grid electrode composed of a cylindrical lattice structure rather than being incident to the grid electrode, and then repeats the movement into the center of the grid electrode. It causes gas targets and nuclear reactions to generate neutrons.

However, many simulation tests and experiments have shown that the accelerated ions are concentrated in the center of the grid electrode, causing ions to accumulate in the center of the grid electrode, and thus to the positively charged ions concentrated in the center. Subsequently, the accelerated ions are influenced by the space charges formed to have orbits that refractively disperse away from the original orbits. This phenomenon has a negative effect on the generation of neutrons, which is a limiting factor in increasing the neutron yield, thus counteracting the positive potential due to the space charge formed by the ions concentrated in the center. There is a need for a way to do this.

The present invention is to solve the above problems according to the prior art. That is, an object of the present invention is to accumulate on the electrode center side by supplying electrons to the center of the grid electrode by mounting an electron source inside the grid electrode where positive space charges are accumulated by the ions focused to the center. It is to provide an inertial electrostatic fusion device equipped with an electron source, characterized in that to effectively cancel the positive (+) space charge to minimize the dispersion by the refraction of the ion beam accelerated to the center to increase the neutron yield.

As a technical idea for achieving the above object, the present invention provides a cylindrical vacuum chamber, a cylindrical electrode provided on the inner wall of the vacuum chamber and grounded through the vacuum chamber, and located in the inner center of the vacuum chamber, A grid electrode formed in a lattice structure, a feedthrough provided at one side of the vacuum chamber to apply a negative high voltage to the grid electrode, and an electron source for supplying electrons into the cylindrical grid electrode. The present invention provides an inertial electrostatic fusion device equipped with an electron source.

Inertial electrostatic fusion device equipped with an electron source according to the present invention, by supplying electrons to the space inside the grid electrode using the electron source to effectively cancel the positive space charge inside the grid electrode of the accelerated ions By suppressing the point of refraction and dispersion of the direction of movement to increase the reactivity in the chamber it is possible to increase the neutron generation yield.

In addition, it is possible to increase the neutron yield while maintaining the advantages of the existing inertial electrostatic fusion device, which has a semi-permanent lifespan and is an integrated type of small neutral resource. Can be utilized throughout.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a view showing the configuration of an inertial electrostatic fusion device according to an embodiment of the present invention.

As shown in FIG. 2, the structure of the inertial electrostatic fusion device includes a cylindrical vacuum chamber 210 and a cylindrical electrode 220 provided on an inner wall of the vacuum chamber 210 and grounded through the vacuum chamber 210. And a grid electrode 230 positioned at an inner center of the vacuum chamber 210 and having a cylindrical lattice structure, and provided at one side of the vacuum chamber 210 to apply a negative high voltage to the grid electrode 230. Feed through (240), a power supply (not shown) for supplying power to the feed-through 240, and an electron source for supplying electrons into the cylindrical grid electrode 230 ( 250).

The vacuum chamber 210 is usually formed in a cylindrical shape, the inner wall of the cylindrical electrode 220 is positioned to ensure uniformity of discharge, the vacuum chamber 210 is maintained in a ground state and electrical and cylindrical electrode 220 The vacuum chamber 210 and the cylindrical electrode 220 maintain the same voltage.

The grid electrode 230 is located in the center of the interior of the vacuum chamber 210, but consists of a cylindrical lattice structure, in order to increase the transparency and to make the plasma uniform, is composed of a lattice of uniform intervals, It is preferable to comprise so that the area which an electrode occupies may be 10% or less of a cylindrical peripheral area.

In addition, the grid electrode 230 is electrically connected to the feedthrough 240 located at one side of the vacuum chamber 210 to receive a negative high voltage from the outside. Therefore, a plasma is generated due to a strong electric field formed between the grounded cylindrical electrode 220 and the grid electrode 230 to which a negative high voltage is applied, and the ions present in the chamber toward the grid electrode 230 located in the center of the chamber. Is accelerated. The ions accelerated toward the grid electrode 230 pass through the grid electrode 230 by the transparency of the grid electrode 230 having a cylindrical lattice structure rather than being incident to the grid electrode 230, and again, the grid electrode 230. By repeating the movement to the center, it generates a neutron by causing nuclear reaction with plasma or gas target inside the chamber.

The feed-through 240 is composed of Teflon and a ceramic insulator having good insulation from the outside to maintain electrical insulation from the outside. The feed-through 240 applies a high negative high voltage, usually in the range of several tens of KV to several hundred KV, to the grid electrode 230. Preferably, the negative high voltage is applied to the grid electrode 230 in the range of -50 KV to -300 KV. Is authorized.

The electron source 250 emits electrons into the center of the grid electrode 230 to neutralize positive ions, thereby effectively canceling the positive (+) space charge accumulated by ions focused at the center of the grid electrode 230. Minimize dispersion due to refraction of the ion beams accelerated to the center.

In this case, the electron source 250 is preferably located near both ends of the axial direction of the vacuum chamber 210 in order to prevent damage due to collision with the accelerated ions, and may be installed at one end or both ends. The electron source 250 is inserted into the grid electrode 230 while maintaining electrical insulation with the grid electrode 230.

Various electron sources capable of generating electrons may be used as the electron source 250, but in order to be less affected by the high voltage in the chamber and to be free from the electrical connection state, the photoelectron may be transferred through a thermal electron source or an external laser using a thermal electron emission. It is effective to use photovoltaic resources that emit. In the case of a hot electron source, a high electron current can be obtained, and in the case of a photo electron source, it is free from the problem of electrical connection, so that the electrons emitted from the electron source can be controlled using a high frequency laser.

When the thermal electron source is used as the electron source 250, the grid electrode 230 and the electron are supplied by supplying corresponding power to the electron source 250 through a separate power supply with reference to the voltage applied to the grid electrode 230. It is desirable for the circles 250 to maintain the same potential to generate an overall uniform plasma.

The operation principle of the inertial electrostatic fusion device of the present invention configured as described above will be described with reference to FIG. 3. 3 is an electrical circuit diagram of the inertial electrostatic fusion device shown in FIG.

As shown in FIG. 3, the vacuum chamber 210 and the cylindrical electrode 220 are electrically grounded, and the grid electrode 230 located therein is high through the feedthrough 240 to several tens to hundreds of KV. A negative high voltage is applied. Therefore, a plasma is generated due to a strong electric field formed between the grounded cylindrical electrode 220 and the grid electrode 230 to which a negative high voltage is applied, and the ions present in the chamber toward the grid electrode 230 located in the center of the chamber. Is accelerated.

The ions accelerated toward the grid electrode 230 pass through the grid electrode 230 by the transparency of the grid electrode 230 having a cylindrical lattice structure rather than being incident to the grid electrode 230, and again, the grid electrode 230. ) Will be repeated to the center of the movement. As the ions move, the fusion reaction is caused by particle collisions such as deuterium-deuterium, deuterium-tritium, deuterium-helium 3 and the like to generate high energy neutrons.

At this time, the electron source 250 effectively cancels the positive (+) space charge inside the grid electrode by neutralizing the cations by emitting electrons into the center of the grid electrode 230. Therefore, by suppressing the refraction and dispersion of the movement direction of the accelerated ions in the chamber to increase the overall reactivity in the chamber can increase the neutron generation yield.

Figure 4 shows an electrical circuit diagram of an inertial electrostatic fusion device is installed with an ion implantation port on one side of the chamber as another embodiment of the present invention. As shown in Figure 4, one side of the vacuum chamber 210 is formed with an ion implantation port 260 for implanting ions into the chamber, if necessary, deuterium, tritium, helium 3 ( ^It is configured to supply external ions such as ³ He) into the chamber. When ion, such as deuterium, tritium, and helium 3 ( ³ He), is injected into the chamber from the ion source through the ion inlet 260, the accelerated ion density inside the chamber is increased, thereby increasing the overall reactivity of the chamber. It can increase the neutron yield effectively.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

1 is a plan view showing the configuration of a conventional inertial electrostatic fusion device.

2 is a view showing the configuration of an inertial electrostatic fusion device according to an embodiment of the present invention.

3 is an electrical circuit diagram of the inertial electrostatic fusion device shown in FIG.

4 is an electrical circuit diagram of an inertial electrostatic fusion device having an ion implantation port in one side of the chamber as another embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

210: vacuum chamber 220: cylindrical electrode

230: grid electrode 240: feedthrough

250: electron source 260: ion implantation port

Claims (9)

In the inertial electrostatic fusion device, A cylindrical vacuum chamber; A cylindrical electrode provided on an inner wall of the vacuum chamber and grounded through the vacuum chamber; A grid electrode positioned at an inner center of the vacuum chamber and formed in a cylindrical lattice structure; A feed-through provided at one side of the vacuum chamber to apply a negative high voltage to the grid electrode; An electron source for supplying electrons into the cylindrical grid electrode; Inertial electrostatic fusion device equipped with an electron source, characterized in that comprises a. The method of claim 1, The grid electrode, An inertial electrostatic fusion device equipped with an electron source, comprising a lattice of uniform spacing, wherein the area occupied by the lattice electrode is 10% or less of the area around the cylinder. The method of claim 1, The electron source, Inertial electrostatic fusion device equipped with an electron source, characterized in that to maintain electrical insulation with the grid electrode. The method of claim 1, The feedthrough, Inertial electrostatic fusion device equipped with an electron source, characterized in that the power supply for applying a negative high voltage to the grid electrode through the feed-through is connected. The method of claim 4, wherein In the electron source, A separate power supply is connected, the inertial electrostatic fusion device equipped with an electron source, characterized in that the potential applied to the electron source and the grid electrode is balanced with each other. The method of claim 1, The grid electrode, An inertial electrostatic fusion device equipped with an electron source, characterized in that a negative high voltage of -50 KV to -300 KV is applied. The method of claim 1, The electron source, An inertial electrostatic fusion device equipped with an electron source, characterized in that a hot electron generator. The method of claim 1, The electron source, An inertial electrostatic fusion device equipped with an electron source, characterized by emitting an photoelectron through an external laser. The method of claim 1, In the vacuum chamber, An inertial electrostatic fusion device equipped with an electron source, characterized in that an ion implantation port is installed to inject ions into the chamber.

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